Live Dash stream race condition issue

rhodh commented 5 years ago

Description

When loading live dash stream with autoplay we can get a race condition where paused is called before play request is complete.

Steps to Reproduce

Download the example demo showcasing the error from here.
Startup the project.
Zap between two streams until we get a hang.
Note that during each zap we get an error Caught pending play exception - continuing (AbortError: The play() request was interrupted by a call to pause(). https://goo.gl/LdLk22)

Expected Results

We don't get a "Caught pending play exception" every time we zap and the stream doesn't hang.

Actual Results

Stream hangs after continuous zapping and we get a "Caught pending play exception" every time we zap.

Workaround

In cancelContentPlay() before pausing the player I added

while(video.seeking()) { }

This did fix the issue. But maybe this isn't the correct way to go about resolving the issue. But if it is I'm happy to create a PR for it.

Versions

videojs-contrib-ads version: 6.4.1

Video-js version: 7.2

videojs-ima version: 1.5.1

Platforms

Browsers: Chrome v69

OS/Devices: Windows 10

mysuf commented 5 years ago

Also It misses first loadstart and then, for whatever reason, triggers readyforpreroll twice while adsready was triggered once.

incompl commented 5 years ago

Can this issue be reproduced in the example integration? It is difficult to debug this without a reduced test case, or know which project the issue lies within.

mysuf commented 5 years ago

@incompl I tried it in both videojs-ima (reported above) and also mine integration with same behaviour. I didnt try contrib-ads-example. I guess that it will be related to missing loadstart event which breaks (somehow) contrib-ads internal workflow.

videojs / videojs-contrib-ads